Your friend asks " shall I bet 1000 dollars in Las Vegas tonight? "
You want answer "yes" secretly. You can do it in the following way easily.
Step 1. Write down the binary code of YES as used in computer.
Y E S
01011001 01000101 01010011
( 8 bit binary code)
Step 2. Write some sentences like
"my life is open book. I have no secrets." [30 letters]
Step 3. Let each letter in the sentence represent a bit {binary digit 0 or 1}.
To represent 0, leave the font as it is. To represent 1, make the letter slightly bolder[ you can innovate]. Code the 24 bits in first 24 letters of the sentences. Leave the remaining 6 letters as they are. They may be taken to represent trailing zeros. The sentence looks as given below.
"my life is open book. I have no secrets."
You have communicated YES secretly to your friend in an open channel without giving room to suspicion.
This is the simple form of cryptography{science of secret coding}. Binary digit coding is the successful computer oriented technique used to represent information.
Welcome to the world of encryption and dycription